It doesn't seem entirely fair to say it stems from "marketing". There were and still are plenty of fully functional applications that rely on the filesystem attributes and indexing on BeOS/Haiku.
I'm sure it is way more limited than some original failed vision but limiting scope doesn't have to be a bad thing and I think what they ended up with does live up to the hype in some ways. That said, it certainly also has some flaws like not even being able to efficiently use the index for the built-in file find dialog because of case insensitivity.
Attributes are exposed on the UI level and can be a useful way to organize custom structured data even for an end user: https://www.haiku-os.org/docs/userguide/en/workshop-filetype...
I'm sure it is way more limited than some original failed vision but limiting scope doesn't have to be a bad thing and I think what they ended up with does live up to the hype in some ways. That said, it certainly also has some flaws like not even being able to efficiently use the index for the built-in file find dialog because of case insensitivity.